Alvin Goldman put forward "A Causal Theory of Knowing" in 1967. He said that the knowledge status of a belief depends on the cause (perhaps some event in the external world) that formed the belief.

Ten years later Goldman presented a reliabilist approach to justification. He said:

The theory
focused on the truth-ratios of the process
types used in belief formation, and generally
goes by the name "process reliabilism". In its
simplest form, it says that a belief's justificational status hinges on the psychological
processes that produce it, e.g., perception,
memory, introspection, or various inference
patterns. Beliefs formed by highly reliable
processes are justified; beliefs formed by insufficiently reliable processes are unjustified.
The approach is motivated by examples.
Intuitively, beliefs formed by unreliable processes like sheer guesswork or wishful thinking are unjustified even if their propositional
contents stand in appropriate relations to
evidence beliefs. Process reliabilism contrasts
with traditional theories like foundationalism
and coherentism in being a "historical" theory rather than a "current time-slice" theory.
Foundationalism and coherentism imply that
justificational status is fixed by mental states
held at the time of believing. According to
reliabilism, it's the mental history of a belief that fixes its justificational status.

(A Companion to Epistemology, 2nd ed., p.144)

As David Armstrong pointed out a few years later (1973), Frank Ramsey had in 1929 suggested both "causal" and "reliable process" theories.

I have always said that a belief was knowledge if it was (i) true, (ii) certain, (iii) obtained by a reliable process. But the word 'process' is very unsatisfactory; we can call inference a process, but even then unreliable seems to refer only to a fallacious method not to a false premiss as it is supposed to do. Can we say that a memory is obtained by a reliable process? I think perhaps we can if we mean the causal process connecting what happens with my remembering it. We might then say, a belief obtained by a reliable process must be caused by what are not beliefs in a way or with accompaniments that can be more or less relied on to give true beliefs, and if in this train of causation occur other intermediary beliefs these must all be true ones.

In 1986, Goldman published Epistemology and Cognition, in which he defended a naturalized version of epistemology. He argued for separate refined treatments of reliabilism, dealing with both knowledge and justification. He also distinguished type reliabilism (he called this "global" reliability) from token-directed model reliabilism ("local reliability).

Goldman argued that epistemology needed help from cognitive science. Years earlier, Willard Van Orman Quine had called for help from the methods of natural science, and thought that epistemology should be "replaced" by psychological science. Goldman says that "historical philosophers never drew a distinction between epistemology and (what is today) called psychology.

In modern times, epistemology
should take notice of what cognitive science
says about the mechanisms or heuristics of
belief formation, both their strengths and
their infirmities (Goldman, 2002 a). This way
of naturalizing epistemology contrasts with
Quine's (1969) way by preserving both
the analytic and the normative aspects of
epistemology.

(A Companion to Epistemology, 2nd ed., p.144)

Quine responded to criticisms that he ignored the normative aspects of epistemology.